This invention relates to an improved catalyst for the reforming of methanol to hydrogen and carbon monoxide and a process of preparing the same.
In conventional catalysts for the reforming of methanol to hydrogen and carbon monoxide, an active alumina base inorganic material is usually used as the material of the catalyst support or carrier. As for the catalytic substance to be deposited on the carrier it is popular to employ a metal or metals of the platinum group, and it is also known to use a base metal or base metals such as copper, chromium, nickel, manganese and/or zirconium instead of, or jointly with, the metal(s) of the platinum group. In such conventional catalysts, platinum, rhodium and palladium have been taken as particularly advantageous in terms of both the conversion efficiency or catalytic activity and the durability in vaporized and heated methanol.
From a practical point of view, however, the conventional catalysts are still unsatisfactory, especially when used in internal combustion engine systems using the reformed gas produced from methanol, in their activity, durability and selectivity for the intended decomposition reaction of methanol to hydrogen and carbon monoxide even though metals of the platinum group are used as the catalytic substance. Therefore, there is a trend toward the use of a considerably large amount of noble metal in producing the catalysts of the above described type with a view to improving the activity and durability of the catalysts, particularly the activity at relatively low temperatures and durability under practical reforming conditions or adaptability to the reforming processes in which vaporized methanol is passed through a catalyst column or bed at a relatively high space velocity. However, such compensative measures are of limited effect and inevitably lead to a considerable rise in the production cost of the catalysts, which offers a serious problem to the reforming of methanol on the commercial basis.